Humanity has now officially reached interstellar space, according to a historic NASA announcement today that the Voyager 1 spacecraft has left the solar system. Thus the much-debated is-it-or-isn’t-it status of Voyager over the past few years has been firmly resolved — and the 36-year-old probe may have some of its most interesting science years still ahead of it.

New and unexpected data indicate Voyager 1 has been traveling for about one year through plasma, or ionized gas, present in the space between stars. Voyager is in a transitional region immediately outside the solar bubble, where some effects from our sun are still evident. A report on the analysis of this new data, an effort led by Don Gurnett and the plasma wave science team at the University of Iowa, Iowa City, is published in Thursday’s edition of the journal Science.

The data came courtesy of a fortuitous coronal mass ejection from the sun in March 2012. The force of this ejection, when it hit Voyager in April 2013, vibrated the surrounding plasma, which the instruments on the spacecraft were able to measure. From that measurement scientists determined that the plasma was more than 40 times denser than what Voyager had encountered in the outer layer of the heliosphere — a density on par with that expected in interstellar space.

The instrumentation that detected the vibrations, amazingly, included an eight-track tape recorder, reports the LA Times:

The antennas, which are connected to a radio transmitter, detect the oscillation, or vibration, of excited plasma particles. The device will convert the oscillations into an audible noise that is recorded on Voyager’s vintage eight-track tape recorder. The frequency of the noise is associated with a specific density of plasma. The higher the frequency, the denser the plasma.

Looking back through the data, the Voyager team believes the big day, when Voyager actually crossed the boundary into interstellar space, was probably August 25, 2012.

That’s an anniversary the craft will be able to celebrate for many years to come, scientists hope. The New York Times reports that study author Edward Stone “expects Voyager 1 to keep sending back data — with a 23-watt transmitter, about the equivalent of a refrigerator light bulb — until roughly 2025.”

This is one refrigerator light bulb we hope will stay on. Kudos Voyager — and godspeed!

Congratulations to NASA and their partners for a truly remarkable feat!!

Tom

Congratulations to the American people for providing their hard-earned tax dollars for making this grand mission possible.

http://blogs.discovermagazine.com Mike Andrews

Richard Feynman once wrote, “it isn’t the stuff, but the power to make the stuff that matters.” Tax issues aside, what’s important is that the American people made it. It is a hell of an accomplishment and shouldn’t be dragged down into petty political arguments that have their root in TODAY’S zeitgeist and have nothing to do with what was happening in the world in the 70’s. I, for one, was happy to have contributed my tax money back then. Today, well that’s a different matter and we would probably be more or less in agreement regarding your implied cynicism…

http://blogs.discovermagazine.com Jeremy Ramsey

It has left the heliosphere, and entered interstellar space, but it still must pass through the Oort cloud to leave our solar system. It will take a couple hundred years or so to reach the Oort cloud, and several thousand more cross it.

Pinche9853

Does the Oort cloud exist?

Loren Riley

Love this article! Also, thank you for including the audio recording! It gave me goosebumps.

Brotherman7

It will take Challenger with a 18,500 mph velocity 26,000 years to travel one light year. 60,000 mph is one percent (1%) light speed. We are in the Triassic Period regarding the technology capable of interstellar let alone intergalactic space travel, as according to scientific calculation matter traveling at light speed is impossible. According to Hawkins this planet only has 5000 million years until our star novas. I’m confident people will find somewhere to go way before then.

DeathK

Our sun will not supernova. It is not massive enough. In about 5 and a half billion years from now it will start a chain of events leading it into a red giant phase and then eventually a white dwarf.

Jennifer Anne Bangstrom

I’m pretty sure I recall the sun will go into what is called a Champagne Supernova.

wendorms

Mine and my brother’s names are on the disk that is affixed to the little spacecraft and it’s pretty wild to know that we have gone, if in name only, extrasolar on that insanely durable craft.
Wendl & Cornel Ormsby

Tom

Can someone answer two questions? First, what is the status of Voyager 2? Second, I remember reading that one or both Voyagers have nuclear propulsion engines; so, how long will these engines last? How long will the nuclear fuel last? What is the type of nuclear fuel? Is it uranium?
I would guess that these spacecraft are “coasting” through space and therefore, it is not necessary for the craft to use their engines for course corrections—especially now that they are pretty much on their own. Comments?